1. Field of the Invention
This invention relates to security devices for homes and commercial buildings and more particularly, to a floor-mounted door lock of the barricade design for securing an inwardly-swinging door while the structure is occupied. The floor-mounted door lock is simple in design, having no moving parts and is portable, positive in operation and easy to use. In a first preferred embodiment the floor-mounted door lock includes a floor anchor secured to the floor of the structure near an entrance door threshold and in the path of swing of the door and an anchor wedge which interlocks with the floor anchor to prevent the door from swinging open. In another preferred embodiment of the invention an elongated threshold plate is configured to engage a raised door threshold on the outside of the structure and extend beneath the door and over the threshold for interlocking with an anchor wedge and preventing the door from opening.
One of the problems encountered in securing inwardly swinging doors in structures, including homes and commercial buildings, is that of constructing a lock system, whether of the doorknob barricade, dead bolt or lock set design, which will withstand the leverage of a crowbar or similar tool. Generally, the doorknob prop or barricade security devices are subject to slippage and while the strength of the lock set or dead bolt is usually not in question, construction of the casement or jamb into which the bolt of the lock set or dead bolt is inserted when in locked configuration, is usually suspect. In most cases, the door casing or jamb is simply splintered and broken away as the door is forced open with a heavy crowbar or like tool. Safety chains and other security devices which are mounted to the casing or jamb and the door in removable, interlocking relationship form somewhat more protection, but also suffer from the disadvantage of being attached directly to the inherently weak casing or jamb, where splintering of the wood allows relatively easy access by application of an appropriate tool.
2. Description of the Prior Art
Most of the external door securing devices detailed in the prior art are of the prop barricade type which fit beneath the door knob and extend to the floor to prevent unauthorized opening of the door. An early "Combined Burglar Alarm and Door Securer" of this design is detailed in U.S. Pat. No. 280,501, dated Jul. 3, 1883, to H. M. and C. E. Moore. The device includes a prop, one end of which is designed to engage the door knob and the other resting on the floor, the prop having a bell mounted thereon for sounding an alarm when pressure is applied to the prop by attempted opening of the door. Another door fastener is detailed in U.S. Pat. No. 605,366, dated Jun. 7, 1898, to G. D. Winters, entitled "Barricade Alarm for Doors". The alarm system includes an elongated prop having an engaging device at one end for engaging the door knob and the opposite end of the prop resting on the floor, with a bell system mounted on the prop for sounding an alarm when pressure is applied to the prop responsive to opening the door. U.S. Pat. No. 2,870,281, dated Jan. 20, 1959, to F. E. Mitchell, details a "Burglar Alarm" which is electrically operated and includes a prop, one end of which is mounted on the door knob and the other resting against the floor. A spring is provided in the prop and compresses responsive to pressure applied to the door, to sound an alarm. U.S. Pat. No. 1,346,768, dated Jul. 13, 1920, to S. Richey, details a "Portable Automatic Door Lock and Burglar Alarm" having an engaging fork at each end, with the top engaging fork resting against the door and the bottom against the floor. A pair of chambers are built into the device and two springs are used to activate an alarm system responsive to pressure applied to the door. U.S. Pat. No. 1,467,363, dated Sep. 11, 1923, to W. T. Farall, details a "Combined Door Check and Burglar Alarm". The device includes an elongated, spring-loaded prop having door-engaging and floor-engaging members on the ends and a cartridge mounted in the device against the bias in the spring, such that compression of the spring responsive to opening a door fires a cartridge and not only awakens the occupant, but hopefully deters the burglar. U.S. Pat. No. 3,804,053 dated Apr. 16, 1974, to James R. Gray, details a "Combination Stop and Alarm". The device is designed for mounting on a door or window and pivoting into secured position with the free end resting against the floor or window seat. The device includes a container of pressurized gas combined with a sound generator which is activated upon opening the door or raising the window.
It is desirable to provide a floor-mounted, barricade-type security device for securing an inwardly-swinging door against unauthorized opening in a safe, efficient and highly reliable manner.
It is therefore an object of this invention to provide a floor-mounted door lock of the barricade design which includes a floor-mounted anchor and an anchor wedge which may be removably interlocked with the floor anchor to block the inward swing of the door.
Another object of this invention is to provide a floor-mounted door lock which is characterized by a floor anchor mounted in close proximity to the threshold in a structure within the inwardly-swinging path of the door and an anchor wedge designed to removably interlock with the floor anchor and prevent the door from opening at all or past a predetermined point.
Yet another object of this invention is to provide a floor-mounted door lock which includes a floor anchor adapted for securing to the floor of a structure near the threshold and in the inward path of swing of a door, the floor anchor provided with an upward-standing anchor flange designed to removably register with a corresponding slot located in the bottom of an anchor wedge, such that the anchor wedge interlocks with the anchor plate and prevents opening of the door past a predetermined point.
Still another object of this invention is to provide a floor-mounted door lock which includes a floor anchor having a flange opening and secured to the floor of a structure adjacent to the threshold within the path of swing of an inwardly-opening door and an anchor wedge fitted with a downwardly-extending flange shaped to removably engage the flange opening in the floor anchor and prevent the door from swinging on its hinges past a predetermined point.
A still further object of this invention is to provide a floor-mounted door lock which is characterized by an elongated, flat threshold plate fitted with a reverse bend at one end for engaging the outside edge of the raised threshold of a door at the exterior of the structure and extending transversely between the door and threshold, with an upward-standing anchor flange or slot provided in the opposite end of the threshold plate inside the structure for removably engaging an anchor wedge and securing the anchor wedge in position to prevent opening of the door past a predetermined point.